(a) Technical Field
The present disclosure relates to an apparatus for manufacturing a liquid crystal display (LCD).
(b) Discussion of the Related Art
An LCD is one of the most widely used flat panel displays. The LCD is a display device that may include two display panels each with an electric field generating electrode formed thereon and a liquid crystal layer interposed therebetween. Liquid crystal molecules of the liquid crystal layer are re-aligned by applying a voltage to the electrodes to thereby control transmittance of light that passes through the liquid crystal layer.
Upper and lower substrates of the LCD can be coupled together by a sealant which is formed on circumferential edges of the substrates. The sealant seals a liquid crystal material between the substrates. The upper and lower substrates can be supported by spacers provided therebetween to sustain a cell gap therebetween.
The spacers can be spherical bead spacers formed in an irregular pattern and column spacers formed in a uniform pattern.
The column spacers are formed in a desired pattern corresponding to portions of pixels where light is not transmitted, namely, for example, a channel portion, a gate line, a storage electrode line, or a light blocking member. The column spacers may be formed after coating a photosensitive film on a color filter array panel and then exposing and developing it.
The bead spacer forming method includes spreading the bead spacers irregularly. As a result of the bead spacer forming method, the bead spacers can act as foreign particles, thereby causing a light leakage that deteriorates the contrast ratio. Also, some bead spacers may undesirably move slightly to damage an alignment layer.
The column spacer forming method requires an additional photolithography process. As a result, a unit cost of a product increases. In addition the column spacers have a smaller elastic force than plastic bead spacers. As a result, a liquid crystal deposition amount margin is reduced to cause a filling deficiency or a smear deficiency when the spacer or a lower film is broken.
A color filter of a color filter array panel, the column spacer, or a light blocking member of the LCD can be fabricated by using a photolithography process. However, the necessity of performing many processes such as thin film coating, exposing, developing, and baking processes, and using many process facilities, are factors for increasing the unit cost of the LCD.
In order to fabricate the color filter array panel without performing the photolithography process, a roll printing process has been developed. However, when the roll printing process is performed, costly color filter ink, spacer ink, or light blocking member ink are not re-used in most cases.